Compactors used for compacting waste have been well known for many years. These compactors utilize a hydraulic ram positioned in a chamber to compact the waste into a denser form. The hydraulic ram compacts the waste against a solid surface within the chamber. In addition to compacting the solid material, a portion of the liquid contained in the waste material may be extracted from the solid waste when pressure is applied by the hydraulic ram. The extracted liquid is discharged from the chamber via drainage slots, grates or holes located in the chamber. Self-contained compactors are typically used for the storage and removal of solid waste containing liquid waste. By regulation, these compactors are designed so that the compactor is attached to a waste container for storage of the compacted waste and the entire system is hauled to the waste disposal site. This eliminates any cross-contamination between the liquid waste and the environment while disposing of the waste. During the compaction process, waste is reduced in volume by removing the air voids located within the waste bulk. A typical compaction ratio of the waste achieved is 3:1.
The compaction of waste is economically advantageous because it significantly reduces the cost of waste disposal for large producers of waste, such as supermarkets, malls, large restaurants, hotels, hospitals and institutions. However, the costs are still significant. One cost associated with waste disposal is the tipping fee, which is based on the number of instances a waste hauler needs to empty a waste container. This cost may be reduced using a compaction process as it allows for more waste to be stored in a waste container, thereby reducing the number of times a waste hauler needs to empty the waste unit. Another cost is the disposal fee, which is based on the overall weight of the waste stored in the waste container. This cost can be minimized by removing liquid from the waste, thereby reducing the disposal weight.
However, the liquid removed from the waste must be disposed of as well. Liquid waste is typically removed from the compaction chamber either via a pumping mechanism or gravimetrically. The liquid waste is maintained in a separate vessel to be disposed by maintenance personnel or a third party vendor off-site. Disposing of this extracted liquid waste off-site induces further costs however these costs are still substantially less than the fees associated with maintaining the liquid waste within the solid waste. Further issues that arise with extracting the liquid waste during compaction and later disposing of the liquid waste off-site include the requirement of additional footprint for liquid waste storage on-site and the logistics for the solid waste generator to store the liquid waste.
Certain waste compactor systems have incorporated liquid evaporation in order to dispose of the liquid waste on-site after being extracted from the solid waste during compaction. These systems address, to some extent, the issues described above. However, the evaporation techniques utilized in the aforementioned compaction systems are limiting because either they fail to substantially dispose of all the extracted waste liquid, they rely solely on electrically powered heating elements which require a significant amount of energy, or they vaporize the liquid waste by heating the liquid beyond its boiling point. Furthermore, in some instances, the evaporation is performed within the compaction chamber which is not suitable for treating industrial and municipal solid waste containing plastics or other waste with a comparable melting point. Therefore, prior art compactor systems do not provide an overall cost effective and energy efficient solution for waste disposal.